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– 13 –

The following adjustments should be made when a complete

realignment is required or a new picture tube is installed.

These adjustments should be performed with rated power

supply voltage unless otherwise noted.

Controls and switches should be set as follows unless otherwise

noted:

PICTURE control ...........................................................  normal

BRIGHTNESS control ...................................................  normal

Perform the adjustments in the following order :

1. Beam Landing

2. Convergence

3. Focus

4. White Balance

Note :  Test Equipment Required.

1. Pattern Generator

2. Degausser

3. Oscilloscope

................................................................................................................................................................................................................................

normal

In order to reduce the influence of geomagnetism on the
set's picture tube, face it east or west.
Switch on the set's power and degauss with the degausser.

1. Input a white signal with the pattern generator.

Contrast
Brightness

2. Set the pattern generator raster signal to a green raster.
3. Move the deflection yoke to the rear and adjust with the

purity control so that the green is at the center and the blue
and the red take up equally sized areas on each side.
(See Figures 3-1 through 3-4.)

4. Move the deflection yoke forward and adjust so that the

entire screen is green. (See Figure 3-1.)

5. Switch the raster signal to blue, then to red and verify the

condition.

6. When the position of the deflection yoke has been decided,

fasten the deflection yoke with the screws and DY spacers.

7. If the beam does not land correctly in all the corners, use a

magnet to adjust it.
(See Figure 3-4.)

}

Purity control

Red

Blue

Green

Purity control
corrects this area.

Disk magnets or rotatable
disk magnets correct these
areas (a-d).

Deflection yoke positioning
corrects these areas.

a

b

b

c

c

d

d

a

– 14 –

4

BMC (Hexapole) Magnet.
If the red, green and blue dots are not balanced or aligned,
then use the BMC magnet to adjust in the manner described
below.

Preparation :
•

Before starting this adjustment, adjust the focus, horizontal
size and vertical size.

•

Receive dot/hatch signal.

•

Pic mode: Soft.

1. (Moving vertically), adjust the V.STAT magnet so that the

red, green and blue dots are on top of each other at the
center of the screen.

2. (Moving horizontally), adjust the H.STAT VR control so

that the red, green and blue dots are on top of each other at
the center of the screen.

3. If the H.STAT variable resistor cannot bring the red, green

and blue dots together at the center of the screen, adjust the
horizontal convergence with the H.STAT variable resistor
and the V.STAT magnet in the manner given below.
(In this case, the H.STAT variable resistor and the V.STAT
magnet influence each other, so be sure to perform adjust-
ments while tracking.)

1

3

Center dot

R    G    B

R

G

B

H. STAT VR

V. STAT

Magnet

RV702

H. STAT

CV Board

R G

B

R

G

B

R

G B

R

B

R

G

G

G

B

R

B

•

Operation of V. Stat magnet
If the V. Stat magnet is moved in the "a" and "b" arrows, the
red, green and blue dots move as shown below.

BMC (Hexapole)

V.STAT

DY pocket

Purity

V.STAT

BMC

Purity

2

R

R

G

G

B

B

a

a

b

b

b

R

R

G

G

B

B

a

b

a

b

R

R

G

G

B

B

a

a

b

b

b

– 15 –

TLH

Insert

TLH

Correction Plate to DY Pocket (Left or
Right)

YCH

Rotate

YCH

VOL on DY

TLV

Rotate

TLV

VOL ON DY

XCV

Rotate

XCV

Adj core on DY

ON DY:

YCH

TLV

DY pocket

DY pocket

XCV

Before starting this adjustment, adjust the horizontal static

convergence and the vertical static convergence

R B

R B

TLH

TLV

YCH

XCV

B

R

R

B

– 16 –

FOCUS adjustment should be completed before W/B adjustment.
1. Receive digital monoscope pattern.
2. Set "Picture Mode" to "DYNAMIC".
3. Adjust focus VR so that the center of screen becomes

just  focus.

4. Change the receiving signal to white pattern and blue back.
5. Confirm magenta ring is not noticeable. Incase magenta is

very obvious, adjust focus VR to take balance of magenta
ring and focus.

1) Set the PICTURE to normal.
2) Put to VIDEO input mode without signals.
3) Connect R, G and B of the CV board cathode to the

oscilloscope.

4) Adjust BRIGHTNESS to obtain the cathode voltage to the

value below.

5) Adjust G2 (screen) on the FBT until picture shows the point

before cut off.

0 V

Cathode setting voltage:

175 V 

± 2 (VDC)

2.a). WHITE BALANCE ADJUSTMENT
1) Set to Service Mode (Refer Section 4-1: ADJUSTMENTS

WITH COMMANDER).

2) Input white raster signal.
3) Set ABL (49) and VP2 (IF) service mode to 00.
4) Set Picture to DYNAMIC.
5) Select RDR (0B) with [1] and [4], and set the level to 25

with [3]  and [6] for best white balance.

6) Select GDR (0C) and BDR (0D) with [1] and [4], and adjust

the level with [3] and [6] for the best white balance.

7) Write into the memory by pressing [MUTING] then [0].
8) Set back ABL (49) and VP2 (IF) service mode to original data.

2.b). SUB BRIGHT ADJUSTMENT
1) Set to service mode.
2) Set ABL (49) and VP2 (IF) service mode to 00
3) Input a staircase signal of black to white from the pattern

generator.

4) BRIGHTNESS .... 50%.

PICTURE ............ MINIMUM

5) Select OE (SBR) with [1] and [4], and adjust OE (SBR) level

with [3] and [6] so that the second stripe from the right is
dimly lit.

6) Write into the memory by pressing [MUTING] then [0].
7) Set back ABL (49) and VP2 (IF) service mode to original

data.

White

second from the right

Black

FOCUS

SCREEN

a

d

c

b

a to d : Permalloy assembly

Fix a Permalloy assy
corresponding to the
misconverged areas

b

a

c

d

a-d : screen-corner
        misconvergence